How to Set Default Email Address in Mail for Mac OS X

Mac users who have multiple email accounts setup with the Mail app may wish to change or set the default email address that is used throughout Mac OS X. This can help to prevent accidentally sending an email from the wrong email address, which should be particularly helpful for those who juggle work and personal email accounts within the Mail app.

What this is going to do is set the default email account for any new email message composition in the Mail app. That includes new mail compositions created from within Mail.app and also elsewhere in Mac OS X, like a mailto link in a web browser or another app. To be clear, this does not disable the other email accounts or disallow their use in Mail app, it simply sets the preferred address to be the default for mail. Even after setting this you can continue to switch mail addresses easily in compositions.

Changing the Default Email Account in Mail for Mac

You obviously need multiple email accounts setup on the Mac for this to be an option, aside from that this process is the same with any modern version of Mail app for Mac:

1. Open Mail app in Mac OS X if you haven’t done so already
2. Pull down the “Mail” menu and choose “Preferences”
3. Go to the “Composing” tab
4. Look for “Send new messages from:” and pull down the ‘Account of selected mailbox’ dropdown menu to select the email address to use as the new default



5. Close out of Preferences when finished

Now the next time you go to compose a new email message, either from Mail app or elsewhere, that email account selected will be the new default email address that any new mail is sent from. If the chosen email account uses an HTML signature, that will also be included by default with each new mail message.

For those of us who use Mail for personal and professional email accounts, this setting pairs well with always showing the complete full name and email address of recipients in Mac Mail so that you can be sure you’re not only defaulting to writing from the proper email address, but also sending and corresponding to the proper addressee.

By the way, if you’re adjusting this on the Mac you’ll almost certainly want to change the default email account on iPhone and iPad too, assuming you use the same email addresses on the go as well.